1. Field of the Invention
One embodiment of the present invention relates to a display device, particularly a liquid crystal display device including a liquid crystal element.
Note that one embodiment of the present invention is not limited to the above technical field. The technical field of one embodiment of the invention disclosed in this specification and the like relates to an object, a method, or a manufacturing method. In addition, the present invention relates to a process, a machine, manufacture, or a composition of matter. In particular, one embodiment of the present invention relates to a semiconductor device, a display device, a light-emitting device, a power storage device, a memory device, a driving method thereof, or a manufacturing method thereof.
In this specification and the like, the display device refers to any device having a display function. The display device may include a semiconductor element such as a transistor, a semiconductor circuit, an arithmetic device, a memory device, and the like. The display device also includes a driver circuit for driving a plurality of pixels, and the like. The display device also includes a control circuit, a power supply circuit, a signal generation circuit, and the like which are provided over another substrate.
2. Description of the Related Art
Transistors used for most flat panel displays typified by a liquid crystal display device and a light-emitting display device are formed using silicon semiconductors such as amorphous silicon, single crystal silicon, and polycrystalline silicon provided over glass substrates. The transistors formed using such silicon semiconductors are also used for integrated circuits (ICs) and the like. In recent years, attention has been drawn to a technique of forming transistors in which a metal oxide having semiconductor characteristics is used instead of a silicon semiconductor. In this specification, a metal oxide having semiconductor characteristics is referred to as an oxide semiconductor. For example, a technique is disclosed in which a transistor is formed using zinc oxide or an In—Ga—Zn-based oxide as an oxide semiconductor and the transistor is used as a switching element or the like in a pixel of a display device (see Patent Documents 1 and 2).